Under iOS 8, All Third-Party Web Browsers Can Be As Fast As Safari

Apple might have improved Safari's performance with iOS 7, but Cupertino restricted this development meaning third-party Web browsers couldn't achieve the same level of power as Apple's own Safari app. Fortunately, however, this has now changed as of iOS 8.
The news reached us in a Twitter update from Vicki Murley (@vickimurley) (via 9to5mac), which surfaced online following a WWDC conference session on iOS 8's WebKit API.
She said:

A few teasers: API is the same across iOS and OS X, and the new WKWebView on iOS is running JS just as quickly as Safari.